Surface finishing operations, such as polishing or buffing, can produce unintended and undesired results. For example, over-polishing can cause pitting to form on a cosmetic surface of a part, thereby causing the over-polished surface to fall outside a desired specification (e.g., undesired aesthetic finish). In many cases, this type of defect can result in a total loss of the part. Determining a cause for the defect can often be difficult. One technique involves assigning an inspector to manually inspect a finished product (e.g., a polished workpiece) after the operation is complete. When a defect is detected, the inspector provides feedback to a machine operator. The machine operator can then make an educated guess as to why the defect occurred and adjust the operation accordingly. However, it is often difficult to ascertain where and why the defect occurred, particularly when the operation contains many steps.
Therefore, what is desired is an improved method for monitoring operations and characterizing causes for defects when performing surfacing operations on a workpiece.